Journal of Marine-Earth Science and Technology

SLOW STEAMING IMPACT ON CONTAINER SHIP’S FUEL CONSUMPTION AND CARBON EMISSION, CASE STUDY: SURABAYA-MAKASSAR ROUTE

Haikal Anjasmara — 2024-04-22

This research investigates the implementation and environmental impact of "slow steaming" as an innovative method in maritime transportation, focusing on the route from Surabaya to Ambon. Utilizing a container ship model with a capacity of 100 TEUs, the study examines resistance data, engine power requirements, and the selection of a main engine aligned with sustainability goals. Slow steaming's influence on fuel consumption and emissions is analyzed, emphasizing cost-effectiveness and environmental benefits. The study extends to sailing route calculations, highlighting reduced oil consumption during slow steaming. Additionally, the research calculates the Energy Efficiency Existing Ship Index (EEXI), crucial for assessing and improving energy efficiency in compliance with International Maritime Organization regulations. The analysis of the container ship scenarios reveals optimal operational conditions and financial performance. In the Round-trip Full Load scenario, peak profitability is achieved at 77% engine load (10.5 knots), yielding Rp50,376,332,800.00 profit. In the Round-trip 1.5 Load scenario, maximum profit occurs at 54% engine load (9.5 knots), resulting in Rp21,245,220,000.00 profit. Bunkering costs, constituting 30-50% of the total cost, significantly influence economic dynamics. The Energy Efficiency Existing Ship Index (EEXI) peaks at 11 knots (31,166.06552) and reaches a minimum at 9.5 knots (22,518.17557). These insights offer guidance for optimizing maritime operational parameters and financial outcomes.

APPLICATION OF SLOW STEAMING ON 100 TEUs CONTAINER SHIP ON THE TANJUNG PERAK-BELAWAN ROUTE

Fajar Andinuari — 2024-07-27

Sea transportation is a vital component of international trade, constituting over 80% of global cargo movement. As the shipping sector anticipates a promising future amid economic liberalization and enhanced operational efficiency, the focus on reducing fuel consumption becomes paramount. This paper investigates the potential benefits and drawbacks of implementing slow steaming, a strategy involving reduced ship speeds, to curtail operational costs, particularly fuel expenses that constitute 47% of total ship operational costs. The liner shipping industry in Indonesia is examined as a case study, evaluating the impact of slow steaming on fuel consumption, emissions, and overall financial performance. Ship that was used in this paper is a 100 TEUs container ship with 2 x 1550 HP engine Yanmar 12AYM-WET which had a voyage route that is assumed to be direct from Tanjung Perak Port to Belawan Port without any transit at other ports. There are 6 speed variations from sea trial data to calculating fuel consumption. Another assumption used is that the dwelling time at Belawan port as of December 2023 is 2.89 days. Considering the dwelling time at Belawan Port, Medan, the speed chosen is 7.6 knots with a travel time of 8.16 days. The assumption is that the fuel used is Diesel Oil B35 with a price of Rp. 22,300/litre. The fuel savings with a travel time of 8.16 days is 19,283.13 litres. The RPM ratio in existing conditions is 1:1.3. So the conversion is carried out into a graph to get the existing FOC. Next, the FOC calculation is carried out by interpolating the fuel consumption diagram against RPM. The CII value at a speed of 7.6 knots shows 0.593 with an A rating. The EEXI value when the speed is 7.6 knots shows the number 7.1235 which is compliant.

WELDING QUALITY CONTROL USING THE FAILURE MODES AND EFFECTS ANALYSIS (FMEA) METHOD AT PT. X

M.Raja Shafa Aulia Jalal Jalal — 2024-09-19

This research aims to identify and analyze defects in the welding process at PT. X uses the FMEA method. The primary defects found were cracks, porosity, spatter, and undercut. The leading causes of crack defects are poor material conditions, porosity caused by inadequate facilities, spatter due to inappropriate parameter settings, and undercut due to lack of supervision. The highest RPN value is crack, with a score of 288, followed by porosity (280), spatter (196), and undercut (175), indicating that crack and porosity require special attention. Improvement strategies include improving material quality and inspection procedures for cracks, improving facilities for porosity, operator training and automated monitoring for spatter, and increased monitoring for undercuts. Based on the visualization of the Pareto diagram, the number of defects that frequently occurred was spatter in 16 cases with a percentage of 36%, followed by undercut in 11 cases (25%), crack in 9 cases (21%), and porosity in 8 cases (18%). This data was collected from production that experienced defects from January – April 2024. The Pareto diagram shows that spatter is the most frequently occurring defect, even though it has a lower RPN than crack and porosity. Therefore, the repair priority must remain on crack and porosity because of their significant impact on weld quality. Implementing the proposed improvement strategy is expected to reduce the risk of failure and increase the efficiency and quality of the welding process at PT. X.